Accessing company records associated with a contact

Trying to show on a menbership website a company custom field that is associated with a contact. ie the value of a company field that relates to a contact. Memberium guys confirm it cant be done via a shortcode. Anyone know of a work around such as create an api connection into another database which we could then link to the website?
Any suggestions welcome as its a bit of a critical issue for us.
Many thanks